A private education company run by a former head of Ofsted has told investors that the coalition's expansion of academies and creation of free schools will create more opportunities for private firms to make money.

Wey Education's statement to potential investors says the government plans will "create increased opportunities for private sector companies to manage and run state-funded schools at all levels".

It also says it can deliver better teaching at lower cost in failing schools, as it has identified "significant savings" in secondary schools' existing financial models.

Wey Education, which is led by the former chair of Ofsted Zenna Atkins, intends to "play a major role as an outsource provider of management services to schools providing state education … taking control of all aspects of the day-to-day running of such schools".

While free schools may not be run for profit, they can contract out school management to private for-profit companies.

The government has received 281 applications to open free schools from September 2012. These included a proposal from Everton FC to open a school that would use sport to engage children at risk of exclusion.

Speaking at the Policy Exchange thinktank in London on Monday, the education secretary, Michael Gove, said: "Even when there are places at local schools, they're not necessarily the type of school places parents are happy with. A choice between two things you don't want is hardly a choice at all. Free schools offer a genuine alternative – and they have the freedom to be different."

Like academies, free schools can set aside the national curriculum and vary teachers' pay and conditions. Many propose to extend teachers' hours to give children a longer school day.

Gove was accompanied at the speech by Michael Wilshaw, headteacher of Mossbourne academy in Hackney, east London, who is proposing an overflow free school to cope with demand from parents. Wilshaw said: "We turn away over 1,000 children every year. It will be a Mossbourne two, in the south of the borough, where provision is not that good, offering a balanced and broad curriculum. Our aim is that 70% will do the English baccalaureate."

Free schools were the most prominent part of Cameron's "big society" idea, encouraging parents and teachers to create their own schools. But earlier this year application rules were tightened up in a way that made it more challenging for community groups.

Detailed financial proposals now have to be presented in the initial application, before groups are eligible for grants to help with planning.

Critics seized on details of Wey Education's statement as an indication that rather than empowering parents, free schools will allow state schooling to be privatised. Mary Bousted, general secretary of the Association of Teachers and Lecturers, said: "This is about the private sector coming in and raking off profits and assets from schools, taking taxpayers' money away from state education."

Atkins, chief executive of Wey Education, said that companies brought in to run academies or free schools would be held to account for pupils' results, meaning they could not simply cut costs without risking losing business. She said: "Half of children are failing to get five good GCSEs including English and maths. When you have a state sector in this country which has failed to do that, I really think the profit motive is a red herring."

However, Gove's speech on Monday was attended by a number of parent and teacher-led free school groups.

Kerstyn Comley, one of thea parent involved in a free school proposal for Wapping, east London, said: "There's a huge shortage of places borough-wide. By 2014 we will be 240 places short. We decided that we had to do something about this as a parents' group."

The Wapping group advocates an extended school day with compulsory afterschool activities, including setting up a newspaper, playing football and polo classes. Comley said: "It will be quite a small school, with 81 students per year. The schools in Tower Hamlets are all pretty large."

She added: "We're not political. We just want a school that's good for our kids."

Like many free school backers, the Wapping group faces a challenge in finding a suitable venue. Comley said: "Where we are is next to the City of London, and if you're looking at private property it's City of London prices."

Tom Shinner, a history teacher working on a free school proposal for Greenwich, south London, said: "Like Mossbourne we'll have high expectations, a 'no excuses' approach. There will be an extended day, from 8am to 5.30pm, and a broad range of extra-curricular activities which every single one of our kids will have to take part in: debating, competitive sport, a model United Nations. We'll have more teachers and fewer non-teaching adults in school, fewer teaching assistants and fewer admin staff."

Rachel Wolf, director of the New Schools Network, said that her group had been "inundated" with applications. A hundred free schools could be created by 2012, and several hundred by 2015, she said.